The bad Yeogo goedam 4

I agree that 'Wishing Stairs' is the most 'horror-like' of the Whispering Corridors series. But for me, that does not make it the best (still in the top two - but not clear cut). After watching all four movies of the 'Whispering Corridor', it seems to me that the series is trying to avoid using the same ingredient often employed in Asian horror (which has it's place - but is arguably all over the place).

For this very reason, I did not immediately appreciate the first of the series, thinking it was too mild. And I disliked Memento Mori even more (even though I was trying to like it). It took a step back further scare wise to the point where I joked about wondering if I was watching Casper the Friendly Ghost (that's when I realised that Whispering Corridor intended to be different). Wishing Stairs decided to take the more classic Asian horror approach by including more scares, a somewhat vengeful spirit, and it did those parts competently. On top of it, I found the characters more memorable if a little confusing during those possessions. So it was instantly my favourite.

My impression of Voice Letter was the opposite of yours. From the beginning, I felt that like the first and second one, it was going to try something different. I was a little worried because 'something different' didn't work for me for the first two. But I was pleasantly surprised. Going by scares, it loses to Wishing Stairs (I think there are a few scene where they really could have made the viewers jump but did not make the most of it e.g. the elevator to where the dark room with voices). However, I made me enjoy Voice Letter is the wide range of emotions I felt during the movie made by the ambiguity of the lead characters (you seem to dislike the movie for this reason, but I loved it for this reason). In Wishing Stairs, it was almost clear cut: the girl who became the ghost was the victim, while her friend mainly bad (regret a little but not enough) and we have a bittersweet ending that ties with the title. Here, we begin by feeling sympathy for the ghost, only to find that she was far from being a saint (and start to despise her). Yet as you've pointed out, the soul we have seen acting throughout the movie, and the person we've seen during Seon-min's flashback was kind. It's not clear cut whether I should sympathise and forgive her, or despise and curse her roam forever as a ghost with no voice. I like the fact that it is not clear cut and emotions were moving back and forth. Personally, I don't think I would've been satisfied with your ending (too simple). That's not to say that I find that I find the movie perfect. Just like with Hye-ju in the third movie, I felt that Cho-ah, while seemingly special/unique at the beginning, were wastefully discarded.